Correlation of Pancreatic Laminin Alpha 5 Expression With Clinical Outcomes in Total Pancreatectomy With Islet Autotransplantation.

This study examines extracellular matrix (ECM) protein (ECM) expression in chronic pancreatitis (CP) patients and its correlation with graft function after total pancreatectomy with islet autologous transplantation (TPIAT). Pancreatic sections from 29 CP patients undergoing TPIAT were analyzed for ECM including pan-laminin, laminin alpha 5 (LAMA5), collagen IV, and Perlecan by immunohistochemistry and scored by the percentage positive staining area within the whole tissue area. Graft function was monitored by blood glucose and C-peptide levels. Laminin alpha 5 levels in blood plasma were greater in CP. Laminin alpha 5 expression was significantly higher in all CP patient etiological categories including alcoholic, hereditary, idiopathic, Oddi dysfunction, and pancreatic divisum compared to healthy controls. The overall expression of LAMA5 positively correlated with expression of the ECM proteins pan-laminin (R = 0.63, P < 0.001), collagen IV (R = 0.67, P < 0.001), and Perlecan (R = 0.71, P < 0.001). Increased LAMA5 expression was observed within islet endothelial vascular tissue and the peri-islet basal membrane. Increased LAMA5 expression in the pancreas correlated with poor islet isolation yield and posttransplant islet function after 3 months. Increased endothelial expression of LAMA5 and ECM proteins is indicative of progressive damage to the pancreas and correlates with poor graft function after TPIAT.